package com.talent.aio.examples.im.common.utils;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;

import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;

public class DesUtils {

	private static byte[] iv = { 1, 2, 3, 4, 5, 6, 7, 8 };

	public static String encrypt(String encryptString, String encryptKey)
			throws Exception {
		IvParameterSpec zeroIv = new IvParameterSpec(iv);
		SecretKeySpec key = new SecretKeySpec(encryptKey.getBytes(), "DES");
		Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
		cipher.init(Cipher.ENCRYPT_MODE, key, zeroIv);
		byte[] encryptedData = cipher.doFinal(encryptString.getBytes());
		return Base64.encode(encryptedData);
	}

	public static String decrypt(String decryptString, String decryptKey)
			throws Exception {
		byte[] byteMi = Base64.decode(decryptString);
		IvParameterSpec zeroIv = new IvParameterSpec(iv);
		SecretKeySpec key = new SecretKeySpec(decryptKey.getBytes(), "DES");
		Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
		cipher.init(Cipher.DECRYPT_MODE, key, zeroIv);
		byte decryptedData[] = cipher.doFinal(byteMi);

		return new String(decryptedData);
	}

	/**
	 * @param args
	 * @throws Exception
	 */
	public static void main(String[] args) throws Exception {
		// TODO Auto-generated method stub
		String key = "fdsfeofa";
		String text = "123ddddddddddddd45678";
		String result1 = DesUtils.encrypt(text, key);
		String result2 = DesUtils.decrypt(result1, key);
		System.out.println(result1);
		System.out.println(result2);
	}

	public static class Base64 {

		private static final char[] legalChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
				.toCharArray();

		/**
		 * data[]进行编码
		 * 
		 * @param data
		 * @return
		 */
		public static String encode(byte[] data) {
			int start = 0;
			int len = data.length;
			StringBuffer buf = new StringBuffer(data.length * 3 / 2);

			int end = len - 3;
			int i = start;
//			int n = 0;

			while (i <= end) {
				int d = ((((int) data[i]) & 0x0ff) << 16)
						| ((((int) data[i + 1]) & 0x0ff) << 8)
						| (((int) data[i + 2]) & 0x0ff);

				buf.append(legalChars[(d >> 18) & 63]);
				buf.append(legalChars[(d >> 12) & 63]);
				buf.append(legalChars[(d >> 6) & 63]);
				buf.append(legalChars[d & 63]);

				i += 3;

//				if (n++ >= 14) {
//					n = 0;
//					buf.append(" ");
//				}
			}

			if (i == start + len - 2) {
				int d = ((((int) data[i]) & 0x0ff) << 16)
						| ((((int) data[i + 1]) & 255) << 8);

				buf.append(legalChars[(d >> 18) & 63]);
				buf.append(legalChars[(d >> 12) & 63]);
				buf.append(legalChars[(d >> 6) & 63]);
				buf.append("=");
			} else if (i == start + len - 1) {
				int d = (((int) data[i]) & 0x0ff) << 16;

				buf.append(legalChars[(d >> 18) & 63]);
				buf.append(legalChars[(d >> 12) & 63]);
				buf.append("==");
			}

			return buf.toString();
		}

		/**
		 * 将二进制转换成16进制
		 * 
		 * @param buf
		 * @return String
		 */
		public static String parseByte2HexStr(byte buf[]) {
			StringBuffer sb = new StringBuffer();
			for (int i = 0; i < buf.length; i++) {
				String hex = Integer.toHexString(buf[i] & 0xFF);
				if (hex.length() == 1) {
					hex = '0' + hex;
				}
				sb.append(hex.toUpperCase());
			}
			return sb.toString();
		}

		public static byte[] decode(String s) {

			ByteArrayOutputStream bos = new ByteArrayOutputStream();
			try {
				decode(s, bos);
			} catch (IOException e) {
				throw new RuntimeException();
			}
			byte[] decodedBytes = bos.toByteArray();
			try {
				bos.close();
				bos = null;
			} catch (IOException ex) {
				System.err.println("Error while decoding BASE64: "
						+ ex.toString());
			}
			return decodedBytes;
		}

		private static void decode(String s, OutputStream os)
				throws IOException {
			int i = 0;

			int len = s.length();

			while (true) {
				while (i < len && s.charAt(i) <= ' ')
					i++;

				if (i == len)
					break;

				int tri = (decode(s.charAt(i)) << 18)
						+ (decode(s.charAt(i + 1)) << 12)
						+ (decode(s.charAt(i + 2)) << 6)
						+ (decode(s.charAt(i + 3)));

				os.write((tri >> 16) & 255);
				if (s.charAt(i + 2) == '=')
					break;
				os.write((tri >> 8) & 255);
				if (s.charAt(i + 3) == '=')
					break;
				os.write(tri & 255);

				i += 4;
			}
		}

		private static int decode(char c) {
			if (c >= 'A' && c <= 'Z')
				return ((int) c) - 65;
			else if (c >= 'a' && c <= 'z')
				return ((int) c) - 97 + 26;
			else if (c >= '0' && c <= '9')
				return ((int) c) - 48 + 26 + 26;
			else
				switch (c) {
				case '+':
					return 62;
				case '/':
					return 63;
				case '=':
					return 0;
				default:
					throw new RuntimeException("unexpected code: " + c);
				}
		}

	}

}